1. Field of the Invention
This invention relates to a fire escape device, more particularly to a fire escape device which is adapted to be supported from a portion of a building structure for alternately lowering people one after another from an elevated floor to a safe location during an emergency situation.
2. Description of the Related Art
Many fire escape devices have been developed to assist people entrapped on elevated floors of a building to safely escape without injury. Some of these devices are difficult to operate in the dark and in emergency situations and cannot permit the rapid escape of people.
The object of the present invention is to provide a fire escape device which is adapted to be supported from a portion of a building structure for alternately and rapidly lowering people one after another from an elevated floor to a safe location during an emergency situation.
According to this invention, the fire escape device includes a mounting shaft secured relative to a portion of a building structure. The mounting shaft defines an axis and has left and right segments opposite to each other in an axial direction parallel to the axis, and an intermediate segment interposed therebetween. A first cable drum includes a first hub portion which is rotatably mounted on the left segment, and which has first left and right ends opposite to each other in the axial direction, and first left and right sidewalls which extend respectively from the first left and right ends outwardly and radially, and which are spaced apart from each other in the axial direction to confine, together with the first hub portion, a first wound region. The first right sidewall has first inner and outer lateral surfaces opposite to each other in the axial direction. A first support cable has a first winding segment to be wound around the first hub portion in the first wound region, a first leading end which extends from the first winding segment and which is adapted to be pulled by a first person on the building structure so as to unreel the first winding segment to rotate the first cable drum in a clockwise direction, thereby lowering the first person to the safe location, and a pulled end which extends from the first winding segment distal to the first leading end and which is loosely anchored relative to the first inner lateral surface and pullable in the axial direction. Immediately after the first support cable is unreeled from the first wound region, the pulled end will be actuated to generate a jerking force in the axial direction. A second cable drum includes a second hub portion which is rotatably mounted on the right segment and which has second left and right ends opposite to each other in the axial direction, and second left and right sidewalls which extend respectively from the second left and right ends outwardly and radially and which are spaced apart from each other in the axial direction to confine, together with the second hub portion, a second wound region. The second left sidewall has second inner and outer lateral surfaces opposite to each other in the axial direction. A second support cable has a second winding segment to be wound around the second hub portion in the second wound region, a second leading end which extends from the second winding segment and which is adapted to be pulled by a next person on the building structure so as to unreel the second winding segment to rotate the second cable drum in a counterclockwise direction, thereby lowering the next person to the safe location, and an anchoring end which extends from the second winding segment distal to the second leading end and which is anchored relative to the second inner lateral surface. A coupling mechanism includes a first coupling member which is disposed on the first outer lateral surface, and a second coupling member which is loosely secured to and which is movable relative to the second outer lateral surface in the axial direction so as to be rotated with the second cable drum about the axis. The second coupling member is sleeved on and is movable relative to the intermediate segment in the axial direction between an engaging position, where the second coupling member is moved to engage the first coupling member so as to rotate with the first cable drum, and a disengaged position, where the second coupling member is retracted to be closer to the second outer lateral surface in the axial direction, thereby disengaging the first coupling member. A biasing member is disposed between the second coupling member and the second outer lateral surfaces to bias the second coupling member to move to the engaging position. A blocking member is disposed on the first outer lateral surface and is movable in response to an axially jerking movement of the pulled end between a blocking position, where the blocking member prevents the second coupling member from engaging the first coupling member against the biasing action of the first biasing member, and an unblocked position, where the blocking member is steered out of the course which permits the engagement between the first and second coupling members.